Quasi-Parallel NiFe Layered Double Hydroxide Nanosheet Arrays for Large-Current-Density Oxygen Evolution...

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Efficient electrocatalysts are vital for water splitting to produce clean hydrogen fuel.
• Achieving high oxygen evolution reaction (OER) activity at large current densities remains a significant challenge for practical applications.

Purpose of the Study:

• To design and synthesize novel quasi-parallel NiFe layered double hydroxide (NiFe LDH) nanosheet arrays on nickel foam for enhanced oxygen evolution.
• To investigate the structure-property relationships governing the electrocatalytic performance of the developed material.

Main Methods:

• Fabrication of quasi-parallel NiFe LDH nanosheet arrays on nickel foam using a coprecipitation method.
• Electrochemical characterization, including cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy, in 1.0 M KOH solution.
• Structural and morphological analysis using techniques such as X-ray diffraction and electron microscopy.

Main Results:

• The quasi-parallel NiFe LDH nanoarrays exhibited excellent OER activity with low overpotentials of 196, 255, and 284 mV at current densities of 10, 500, and 1000 mA cm⁻², respectively.
• The catalyst demonstrated a small Tafel slope of 30.1 mV dec⁻¹, indicating efficient OER kinetics.
• High stability was observed, with the material maintaining performance over 40 hours at a current density of 750 mA cm⁻².

Conclusions:

• The developed quasi-parallel NiFe LDH nanoarrays represent a promising electrocatalyst for efficient and stable oxygen evolution in water splitting.
• The unique nanostructure and electronic properties contribute to the enhanced catalytic performance.
• This work offers a new strategy for fabricating high-performance electrode materials for electrochemical energy conversion.